The invention relates to a slitting tool for a circular saw machine, especially for a panel saw, as well as a slitting saw blade therefor.
Such a slitting tool is used especially when a material having a sensitive or brittle cover layer must be cut by a circular saw blade. When performing a cut, the saw teeth of the circular saw blade may exit from the workpiece cover layer at a relatively flat angle so that at the exit area of the saw blade chipping or tearing may occur at the cover layer.
In woodworking shops or finishing shops, a slitting tool is used first for cutting to size especially laminated material panels by panel saws. The slitting tool rotates counter to the direction of rotation of the saw blade. In a first step the slitting tool separates the chipping prone lower cover layer and generates a slitting groove of minimal depth in which the saw blade for separating the material will enter from above when performing the separating cut. In order to produce a straight and chip-free edge at the material panel at the exit side of the saw blade, the center axes of the two tools must be positioned on a single straight line and their cutting widths must be adjusted to one another.
Panel saws are also used for materials with edges that are chip-resisant. In these cases, the slitting tool is pivoted away and only the circular saw blade is used. Accordingly, the circular saw blade is subjected to greater wear and must be sharpened more frequently whereby the cutting width of the circular saw blade changes and the resulting measurement differences must be compensated by a cutting width adjustment of the slitting tool.
Known slitting tools used with panel saws are comprised of two blade halves and spacer rings positioned therebetween whereby the blade halves form the slitting saw blade and are clamped between two flanges on a drive shaft. The adaptation of the cutting width of the slitting tool to the actual cutting width of the circular saw blade is performed by removing or adding one or more spacer rings. In practice, the cutting width of the newly sharpened circular saw blade is first measured. Subsequently, the slitting tool is removed from the drive shaft, dismantled, and the required number of spacer rings are arranged. The blade halves of the slitting tool are then mounted so as to be rotationally and axially secured on the drive shaft. When in a subsequent tryout the width of the cut of the slitting tool does not yet match, the slitting tool must again be removed and disassembled in order to exchange the respective spacer rings to adjust for the deviation. The adaptation of the cutting width is thus time and labor intensive. Moreover, when a plurality of trial cuts are required for the adjustment, a considerable amount of waste material is produced.
From European patent application 0 273 200 a circular saw blade with adjustable cutting width is known in which the blade halves are secured on a respective tool flange. The tool flanges are embodied so as to be of radial symmetry and are adjustable with an exterior adjusting device axially relative to one another so that the cutting width of the circular saw blade can be changed. The entire arrangement, however, is very large especially because of the exterior adjusting device so that it can be used only with difficulty as a slitting tool because of the minimal space available at panel saws.
It is therefore an object of the invention to improve a slitting tool, and a slitting saw blade for such a slitting tool of the aforementioned kind such that for a minimal constructive size an adjusting device for a fast and simple adjustment of the cutting width with respect to a circular saw blade downstream thereof is possible with minimal labor expenditure.